#!/bin/bash
# See: https://github.com/kward/shunit2

argImage=$1
argOutput=${2:-"quiet"}
argCleanup=${3:-"cleanup"}
testDir="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
imageName="$argImage"
tmpDir="$(mktemp -d /tmp/atmoz_sftp_XXXX)"
sshKeyPri="$tmpDir/rsa"
sshKeyPub="$tmpDir/rsa.pub"
sshHostEd25519Key="$tmpDir/ssh_host_ed25519_key"
sshHostKeyMountArg="--volume=$sshHostEd25519Key:/etc/ssh/ssh_host_ed25519_key"
sshKnownHosts="$tmpDir/known_hosts"

if [ $UID != 0 ] && ! groups | grep -qw docker; then
    echo "Run with sudo/root or add user $USER to group 'docker'"
    exit 1
fi

if [ ! -f "$testDir/shunit2/shunit2" ]; then
    echo "Could not find shunit2 in $testDir/shunit2."
    echo "Run 'git submodule update --init'"
    exit 2
fi

if [ -z "$argImage" ]; then
    echo "Missing image name"
    exit 3
fi

if [ "$argOutput" == "quiet" ]; then
    redirect="/dev/null"
else
    redirect="/dev/stdout"
fi

# clear argument list (or shunit2 will try to use them)
set --

##############################################################################
## Helper functions
##############################################################################

function oneTimeSetUp() {
    # Generate temporary ssh keys for testing
    if [ ! -f "$sshKeyPri" ]; then
        ssh-keygen -t rsa -f "$sshKeyPri" -N '' > "$redirect" 2>&1
    fi

    # Private key can not be read by others (sshd will complain)
    chmod go-rw "$sshKeyPri"

    # Generate host key
    ssh-keygen -t ed25519 -f "$sshHostEd25519Key" < /dev/null
}

function setUp() {
    # shellcheck disable=SC2154
    containerName="atmoz_sftp_${_shunit_test_}"
    containerTmpDir="$(mktemp -d "/tmp/${containerName}_XXXX")"
    export containerName containerTmpDir

    retireContainer "$containerName" # clean up leftover container
}

function tearDown() {
    retireContainer "$containerName"

    if [ "$argCleanup" == "cleanup" ] && [ -d "$containerTmpDir" ]; then
        rm -rf "$containerTmpDir" || true # Can fail on GitHub Actions
    fi
}

function retireContainer() {
    if [ "$(docker ps -qaf name="$1")" ]; then
        if [ "$argOutput" != "quiet" ]; then
            echo "Docker log for $1:"
            docker logs "$1"
        fi

        if [ "$argCleanup" == "cleanup" ]; then
            docker rm -fv "$1" > "$redirect" 2>&1
        fi
    fi
}

function getSftpIp() {
    docker inspect -f "{{.NetworkSettings.IPAddress}}" "$1"
}

function runSftpCommands() {
    ip="$(getSftpIp "$1")"
    user="$2"
    shift 2

    echo "$ip $(cat "$sshHostEd25519Key.pub")" >> "$sshKnownHosts"

    commands=""
    for cmd in "$@"; do
        commands="$commands$cmd"$'\n'
    done

    echo "$commands" | sftp \
        -i "$sshKeyPri" \
        -oUserKnownHostsFile="$sshKnownHosts" \
        -b - "$user@$ip" \
        > "$redirect" 2>&1

    status=$?
    sleep 1 # wait for commands to finish
    return $status
}

function waitForServer() {
    containerName="$1"
    echo -n "Waiting for $containerName to open port 22 ..."

    for _ in {1..30}; do
        sleep 1
        ip="$(getSftpIp "$containerName")"
        echo -n "."
        if [ -n "$ip" ] && nc -z "$ip" 22; then
            echo " OPEN"
            return 0;
        fi
    done

    echo " TIMEOUT"
    return 1
}

##############################################################################
## Tests
##############################################################################

function testSmallestUserConfig() {
    docker run --name "$containerName" "$sshHostKeyMountArg" \
        --entrypoint="/bin/sh" \
        "$imageName" \
        -c "create-sftp-user u: && id u" \
        > "$redirect" 2>&1
    assertTrue "user created" $?
}

function testCreateUserWithDot() {
    docker run --name "$containerName" "$sshHostKeyMountArg" \
        --entrypoint="/bin/sh" \
        "$imageName" \
        -c "create-sftp-user user.with.dot: && id user.with.dot" \
        > "$redirect" 2>&1
    assertTrue "user created" $?
}

function testUserCustomUidAndGid() {
    id="$(docker run --name "$containerName" "$sshHostKeyMountArg" \
        --entrypoint="/bin/sh" \
        "$imageName" \
        -c "create-sftp-user u::1234:4321: > /dev/null && id u" )"

    echo "$id" | grep -q 'uid=1234('
    assertTrue "custom UID" $?

    echo "$id" | grep -q 'gid=4321('
    assertTrue "custom GID" $?

    # Here we also check group name
    assertEquals "uid=1234(u) gid=4321(group_4321) groups=4321(group_4321)" "$id"
}

function testCommandPassthrough() {
    docker run --name "$containerName" "$sshHostKeyMountArg" \
        "$imageName" test 1 -eq 1 \
        > "$redirect" 2>&1
    assertTrue "command passthrough" $?
}

function testUsersConf() {
    docker run --name "$containerName" "$sshHostKeyMountArg" -d \
        -v "$testDir/files/users.conf:/etc/sftp/users.conf:ro" \
        "$imageName" \
        > "$redirect" 2>&1

    waitForServer "$containerName"
    assertTrue "waitForServer" $?

    docker exec "$containerName" id user-from-conf > /dev/null
    assertTrue "user-from-conf" $?

    docker exec "$containerName" id test > /dev/null
    assertTrue "test" $?

    docker exec "$containerName" id user.with.dot > /dev/null
    assertTrue "user.with.dot" $?

    docker exec "$containerName" test -d /home/test/dir1 -a -d /home/test/dir2
    assertTrue "dirs exists" $?
}

function testLegacyUsersConf() {
    docker run --name "$containerName" "$sshHostKeyMountArg" -d \
        -v "$testDir/files/users.conf:/etc/sftp-users.conf:ro" \
        "$imageName" \
        > "$redirect" 2>&1

    waitForServer "$containerName"
    assertTrue "waitForServer" $?

    docker exec "$containerName" id user-from-conf > /dev/null
    assertTrue "user-from-conf" $?
}

function testCreateUsersUsingEnv() {
    docker run --name "$containerName" "$sshHostKeyMountArg" -d \
        -e "SFTP_USERS=user-from-env: user-from-env-2:" \
        "$imageName" \
        > "$redirect" 2>&1

    waitForServer "$containerName"
    assertTrue "waitForServer" $?

    docker exec "$containerName" id user-from-env > /dev/null
    assertTrue "user-from-env" $?

    docker exec "$containerName" id user-from-env-2 > /dev/null
    assertTrue "user-from-env-2" $?
}

function testCreateUsersUsingCombo() {
    docker run --name "$containerName" "$sshHostKeyMountArg" -d \
        -v "$testDir/files/users.conf:/etc/sftp-users.conf:ro" \
        -e "SFTP_USERS=user-from-env:" \
        "$imageName" \
        user-from-cmd: \
        > "$redirect" 2>&1

    waitForServer "$containerName"
    assertTrue "waitForServer" $?

    docker exec "$containerName" id user-from-conf > /dev/null
    assertTrue "user-from-conf" $?

    docker exec "$containerName" id user-from-env > /dev/null
    assertTrue "user-from-env" $?

    docker exec "$containerName" id user-from-cmd > /dev/null
    assertTrue "user-from-cmd" $?
}

function testWriteAccessToAutocreatedDirs() {
    docker run --name "$containerName" "$sshHostKeyMountArg" -d \
        -v "$sshKeyPub":/home/test/.ssh/keys/id_rsa.pub:ro \
        "$imageName" "test::::testdir,dir with spaces" \
        > "$redirect" 2>&1

    waitForServer "$containerName"
    assertTrue "waitForServer" $?

    runSftpCommands "$containerName" "test" \
        "cd testdir" \
        "mkdir test" \
        "cd '../dir with spaces'" \
        "mkdir test" \
        "exit"
    assertTrue "runSftpCommands" $?

    docker exec "$containerName" test -d /home/test/testdir/test
    assertTrue "testdir write access" $?

    docker exec "$containerName" test -d "/home/test/dir with spaces/test"
    assertTrue "dir with spaces write access" $?
}

function testWriteAccessToLimitedChroot() {
    # Modified sshd_config with chrooted home subdir
    tmpConfig="$(mktemp)"
    sed 's/^ChrootDirectory.*/ChrootDirectory %h\/sftp/' \
        < "$testDir/../files/sshd_config" > "$tmpConfig"

    # Set correct permissions on chroot
    tmpScript="$(mktemp)"
    cat > "$tmpScript" <<EOF
mkdir -p /home/*/sftp
chown root:root /home/*/sftp
chmod 755 /home/*/sftp
EOF
    chmod +x "$tmpScript"

    docker run --name "$containerName" "$sshHostKeyMountArg" -d \
        -v "$sshKeyPub":/home/test/.ssh/keys/id_rsa.pub:ro \
        -v "$tmpConfig:/etc/ssh/sshd_config" \
        -v "$tmpScript:/etc/sftp.d/limited_home_dir" \
        "$imageName" "test::::sftp/upload" \
        > "$redirect" 2>&1

    waitForServer "$containerName"
    assertTrue "waitForServer" $?

    runSftpCommands "$containerName" "test" \
        "cd upload" \
        "mkdir test" \
        "exit"
    assertTrue "runSftpCommands" $?

    docker exec "$containerName" test -d /home/test/sftp/upload/test
    assertTrue "limited chroot write access" $?
}

function testBindmountDirScript() {
    mkdir -p "$containerTmpDir/custom/bindmount"
    echo "mkdir -p /home/custom/bindmount && \
        chown custom /custom /home/custom/bindmount && \
        mount --bind /custom /home/custom/bindmount" \
        > "$containerTmpDir/mount.sh"
    chmod +x "$containerTmpDir/mount.sh"

    docker run --name "$containerName" "$sshHostKeyMountArg" -d \
        --privileged=true \
        -v "$sshKeyPub":/home/custom/.ssh/keys/id_rsa.pub:ro \
        -v "$containerTmpDir/custom/bindmount":/custom \
        -v "$containerTmpDir/mount.sh":/etc/sftp.d/mount.sh \
        "$imageName" custom:123 \
        > "$redirect" 2>&1

    waitForServer "$containerName"
    assertTrue "waitForServer" $?

    runSftpCommands "$containerName" "custom" \
        "cd bindmount" \
        "mkdir test" \
        "exit"
    assertTrue "runSftpCommands" $?

    docker exec "$containerName" test -d /home/custom/bindmount/test
    assertTrue "directory exist" $?
}

function testDuplicateSshKeys() {
    docker run --name "$containerName" "$sshHostKeyMountArg" -d \
        -v "$sshKeyPub":/home/user/.ssh/keys/key1.pub:ro \
        -v "$sshKeyPub":/home/user/.ssh/keys/key2.pub:ro \
        "$imageName" "user:" \
        > "$redirect" 2>&1

    waitForServer "$containerName"
    assertTrue "waitForServer" $?

    lines="$(docker exec "$containerName" sh -c \
        "wc -l < /home/user/.ssh/authorized_keys")"
    assertEquals "1" "$lines"
}

##############################################################################
## Run
##############################################################################

# shellcheck disable=SC1091
source "$testDir/shunit2/shunit2"
# Nothing happens after this
